The present invention relates to calipering systems for monitoring the delivery of inserts to a gathering or inserting apparatus and more particularly to a novel calipering system including software and hardware for assuring and maintaining caliper accuracy, providing automated setup and providing information for inventory control and for assuring insert zoning accuracy.
Learn-mode calipers have been in service for several years in the book binding industry for monitoring the flow of inserts from a hopper to a gathering machine. However, such prior art systems have been limited to the capability of indicating either a xe2x80x9cmissxe2x80x9d or a xe2x80x9cmultiple feedxe2x80x9d in addition to providing an indication of a xe2x80x9cnormal feedxe2x80x9d.
Such systems lack the capability of providing specific and accurate multiple feed operations such as recognizing simultaneous feeding of two, three, four, five or more inserts.
In addition, present day systems lack the capability of simplified setup of the calipering system as well as maintaining continuing accuracy regardless of ink build-up on the caliper roll and changes in paper basis weight.
The present invention is characterized by comprising hardware which incorporates a dual caliper range technique to further enhance the caliper accuracy through the employment of the first and second caliper ranges each being designated for measuring a predetermined thickness range, such as 0.003 inches to {fraction (5/16)}th inches and {fraction (5/16)}th inches to ⅝th inches using only one proximity sensor.
The calipering system has two operating modes namely a xe2x80x9clearn zeroxe2x80x9d mode and a xe2x80x9clearn insertxe2x80x9d mode. Operating mode selection is obtained through operation of a 3-position manual selector switch. When xe2x80x9clearn zeroxe2x80x9d is selected, the hopper is cycled without feeding inserts to adjust the zero position of the caliper.
Thereafter, prior to feeding the first single insert, the switch is moved to the xe2x80x9clearn insertxe2x80x9d position and is maintained in this position until a new insert is re-learned. During the xe2x80x9clearn insertxe2x80x9d mode, the calipering system is automatically adjusted to the single insert being fed.
The third switch position is reserved for a xe2x80x9ccalibrationxe2x80x9d mode. During regular calipering operation, this position is passive and calibration will be activated if the proper procedure is not followed.
On occasions when the learn mode caliper may have to be recalibrated or in the event the calibration check is desired, the hopper is jogged to activate the timing proximity sensor and the three position switch is moved to the xe2x80x9ccalibratexe2x80x9d position. Light indicators provided as part of the control panel provide either a flashing indication to advise the operator that the caliper is properly calibrated or other light indications which indicate that the caliper requires calibration and pointing out which caliper component is at fault.
The learn sequence is both simple and rapid and is initiated by assuring the first insert fed into the hopper is a single insert which generates an analog insert value to be used by the caliper control program to set the preliminary target values for miss, single, double, triple, etc. As the first insert is xe2x80x9clearnedxe2x80x9d the caliper program warns the operator if the first insert is above or below the caliper operating range.
The control program makes preliminary target computations which are based on parameters that are fixed real numbers which originate from empirical testing and are determined as a function of insert thickness and represent the insert boundaries. As an example, assuming that it is possible to run a one inch insert, the parameters for xe2x80x9cone single feedxe2x80x9d would be 0.5 inches and 1.8 inches, i.e. if a measurement of below 0.5 inches is made, this is considered a miss and if a measurement of above 1.8 inches is made this is considered to be a double.
xe2x80x9cSeedsxe2x80x9d are generated by an algorithm following the first single feed. The caliper program stores the value of the second and third single inserts during the learn sequence. The values for these second and third inserts must be within 10% of the first value recorded by the caliper program. When the three inserts are recorded, the caliper program generates an average single insert (i.e. the three recorded insert measurements are averaged and this is the xe2x80x9cseedxe2x80x9d employed to refine the preliminary target values).
The software provides a continuous insert revision wherein the insert xe2x80x9cseedxe2x80x9d changes constantly to preserve caliper reading integrity which may be altered due to insert thickness variations within a batch. Seeds for inserts ranging in thickness from three to thirty thousandths of an inch are updated every 20 single feeds. Seeds for inserts between 30 and 60 thousandths of an inch thick are updated every 10 single feeds. Seeds for inserts between 60 and 120 thousandths of an inch thick are updated every 5 single feeds and seeds for inserts above 120 thousandth of an inch thick are updated every time a single insert is recorded.
The system provides a continuous zero insert update which continuously updates the zero insert associated with inserts thinner than 80 thousandth of an inch. The update is designed to compensate for any xe2x80x9chopper drum growthxe2x80x9d due to such factors as heat expansion that could result in potential accuracy losses.
The zero insert update is activated after a miss if the offset air cylinder is not energized when the zero update is activated. The caliper program stores mis-values in groups of twenty and then averages the values. If the average values are over plus or minus one thousandth of an inch of the original zero base then the original base is updated, otherwise it is left unchanged.
The caliper system is provided with a cushioned stop for eliminating noise generated by the caliper when running thicker inserts. The cylinder is activated automatically by the caliper program when running inserts thicker than 80 thousandth of an inch or when the hopper is inhibited for six cycles, and is maintained activated until the inhibit is cancelled.
The caliper software program provides for the display of various types of performance data as well as access to the various caliper parameters, variables and seeds used in the algorithms and further provides real time product count by station, per zone, for: miss, 1, 2, 3, 4, 5 or greater insert feeds and the total count polled per hopper, and per zone, having a current capability of up to 10 thousand packages.
The software, in addition to performing all of the above functions, performs a number of electronic tests which insure perfect calibration throughout operation of the caliper system.
It is therefore one object of the present invention to provide a novel caliper system for monitoring inserts delivered from a hopper and identifying with precision the nature of the delivery during each operating cycle (i.e. xe2x80x9cmissingxe2x80x9d, xe2x80x9csinglexe2x80x9d, xe2x80x9cdoublexe2x80x9d, etc. feeds).
Still another object of the present invention is to provide a novel caliper system which includes hardware for xe2x80x9clearningxe2x80x9d an initial caliper setting in the absence of an insert feed.
Still another object of the present invention is to provide a novel caliper system which includes hardware for xe2x80x9clearningxe2x80x9d an initial insert thickness setting in the absence of an insert feed. Still another object of the present invention is to provide a novel caliper system employing dual caliper detection ranges for detecting distinct but adjacent thickness ranges by a single proximity sensor which greatly enhances the accuracy of the caliper system.
Still another object of the present invention is to provide a novel caliper system utilizing software for continuously updating operating parameters to compensate for any changes in paper thickness, ink buildup and the like.
Still another object of the present invention is to provide a novel caliper system utilizing software which performs a plurality of electronic tests during regular intervals to assure proper calibration throughout the calipering operation.
Still another object of the present invention is to provide a novel calipering system which, in addition to providing accurate data regarding the precise nature of inserts delivered during each cycle of operation, further provides data to assist in the evaluation of targeting zones in various types of performance data and parameter data.